Gallium nitride based power devices may be epitaxially grown on silicon substrates. The growth of gallium nitride based power devices on a silicon substrate is a heteroepitaxial growth process since the substrate and the epitaxial layers are composed of different materials. Due to the heteroepitaxial growth process, the epitaxially grown material may exhibit a variety of adverse effects, including reduced uniformity and reductions in metrics associated with the electronic/optical properties of the epitaxial layers. Accordingly, there is a need in the art for improved methods and systems related to epitaxial growth processes and substrate structures.